Radiosignaling apparatus



w. R. DAVIS.

RADIOSIGNALING APPARATUS. APPLICATION man MAR. 9. 191s.

Patented Aug- 16, 1921.

. usireo sures PATIENT o Fic WILLIAM RAY \n vIs, OF'MIN-NEAPOLIS, MINNESOTA, Assrenon mo- THEYW LLIAM .Hoon nnlvwoonrmnnsrnrnr. frnsrrrnrn,

PORATION.

Application :filed March 9,

To all'whomit man concerm 5 Be it known that I, WILLIAM R.-v DAVIS, a citizen of the United States, resident of Minneapolis, county, of Hennepin, State 1 of Minnesota, have invented certain new and useful Improvements in Radiosignaling Apparatus, of which the following isa specification.

The objectof my invention is to provide an apparatus by means of which radio or wireless signalscan be produced for class room work corresponding substantially to the signals a radio operator would be re quired to receive in actual practice. 7

A further object is to provide an apparatus by means of whichradio signals can be transmitted to any number of pupils, all of Whom may receive the same signals. c

A further object is to provide an appa ratus of simple, inexpensive construction and one which can be easily and quickly in stalled in the radio instruction department of any industrial or technical school.

-The invention'consists generally in various constructions and combinations, all as hereinafter described and particularly pointed out in the claims.

In the accompanying drawings forming part of this specification,

Figurelis a diagrammatic view of the signaling apparatus embodying my invention,

Fig. 2 is a front elevation ofthe revolving disk device, showing its position with respect to the stationary magnets,

Fig. 3 is an edge view of the same.

In the drawing, 2 represents a motor of any suitable type and power, having a shaft 3 on which is mounted a disk 4. This disk is preferably ofsteel and is provided with a series of peripheral notches 5 alternating with lugs. or teeth 6. This disk is revolved at any desired speed. Mounted adjacent to the periphery of the disk are a series of magnets 7, substantially U-shaped and suitably spaced apart around the outside of the disk, with sufiicient clearance between their poles and the periphery of the disk to allow free'- dom of'revolution of the disk without contacting therewith. I have shown a few of these magnets at the bottom of the disk, butc it will be understood there may be any desired number grouped around it.

- One of the poles, as at A, has an insulated nnnrosrenanmefnrramrns.

Specification of Letters Patent.

Patented Aug. 1 ,1921. 1918. iserial no. 221,559. I conductorC wrappedzthereon. and circuit with thebattery Bthrongh a; suitable switch S. -;The conductor 0 or vrrnnnnnonrsgivumsoranconpasses from the pole i of the first magnet to the corresponding pole ofthenextone and so on around thedisk,

a suitableinumber of coils of the conductor being provided for each pole and from the pole of the last magnet the conductor extends to ;the battery so that z the correspond ing poles of the magnets are all in series circuit and controlled by the switch S. The other poles of the magnets have independent conductors D wrapped thereon; Each of the conductors 'D has a sending key Ktherein and a series of receivers H are in circuit with the conductors D and located at suitable tables, around which the radio students are seated. There may be any desired number oftables, according to the size of the re-. volving while the pitch or tone of the alternating current produced by the revolution of the disk will be the same in all the circuits while the disk is revolving at a certain speed, the

person controlling the key K in each circuit D increasing or decreasing the speed of sending the signals, according to the capacity of, the students in that circuit to re-' ceive them. Thus one group of students may be seated at a table where the signals are given very slowly, only a few words per minute, the operator at the key regulating the speed of sending according to the ability of the students at the table with which his circuit is connected. Another table may be used for more advanced students, the signals being sent faster and so on through the room until the student reaches a table where the signals have to be received with substantially the same speedas required in actual practice.

When the disk is stationary, it will be understood that the circuits D will be dead, but therevolution of the disk past the ends of the magnets will have the effect of varying the-magnetism and thereby producing an induced current in the circuits D, the,

nets maybe provided for each disk, each I magnet being connected with an independent circuit in which a current is induced through the revolution of the disk.

- I claim as my invention: v 1'. An apparatus of he class described comprising a series or U-shaped magnets, a winding on each pole of saidniagnets, the windings on one pole of each of said magnets being connected in series in an electric circuit, independent conductors connected with the other windings of said magnets andeach having a sending key and anumher of receivers therein, and a series of armatures mounted to revolve in the field of said magnets. g a

2. An apparatus of the class described comprising a series of-U-shaped magnets, a winding on each pole of said magnets, the windings on one pole of each of said magnets being connected in series in an electric circuit, independent conductors connected with the other windings of said magnets and each having a sending key and arnumber of receivers therein, and a disk having a series of armatures mounted; to revolve in the field of said magnets. i

'3. An apparatus of the class described comprising a series of magnets, a winding on each pole of said magnets, the windings on one pole of eachof said magnets being connected in series in an electric circuit, independent conductors connected in parallel with the otherwindings of said magnets and having sending keys and receivers therein, and means for revolving armatures in the field of said magnets.

Inwitness whereof, I have hereunto set my hand this 15th day of February 1918.

' WILLIAM RAY Davis. 

